This invention relates to roll forming machines and, more particularly, to a roll forming machine for producing a rain gutter and which includes an internal gutter guide assembly which is protective of the finish on the face of the gutter.
Roll forming machines for producing rain gutters are generally well known. In such a machine, the gutters are formed from a supply coil of sheet metal which is finished on a first side so that the exterior of the finished gutter has an aesthetically pleasing appearance. As the sheet metal is driven through the machine along a predetermined path of travel, its lateral profile is gradually transformed from a flat sheet into a downwardly concave trough having a desired lateral profile and with the finished side of the sheet metal forming the exterior surface of the trough. During this transformation, the outside of the partially formed gutter is contacted by guide structure to ensure that it moves properly through sets of series of roll forming stations. Up to now, the present face guide design includes a fixed face guide rod, which allowed one to raise the leading edge of the sheet metal as the material is fed through the machine from one set of roll forming stations to the next set of roll forming stations. When both sets of roll forming stations fully engage the sheet metal, the gutter profile being formed will lift up off the face guide rod by approximately up to ⅛″ so that the guide rod does not scratch the surface of the gutter. This works fine for a short span between the sets of roll forming stations because there is enough structural integrity in the gutter profile to maintain a gap between the profile and the guide rod. However, in a machine which has a large span between sets of roll forming stations, the gutter, profile cannot maintain a gap between the gutter profile and the fixed face guide rod. The gutter would simply flex enough over the large span that it would be impossible to maintain a gap between the gutter profile and the face guide rod without putting a permanent detrimental set into the gutter profile itself. Thus, the face of the gutter would scrape along the face guide rod, leading to scratching of the face of the gutter and creating an unsightly appearance. It would therefore be desirable to provide guide structure which allows the gutter face to remain in line with the pass line of the roll forming tool sets without scratching the gutter's finished face.